I am looking to swap my TPI out for a LT1 intake. I have been looking for a good cam choice and came across a few. Anyone using these? If not these cams - what about the numbers? Probably will go with Trick Flow heads or AFR if money permits.

Comp Cams - CS XR276HR-10

Cam Style Hydraulic roller tappet
Basic Operating RPM Range 1,900-5,600 RPM
Intake Duration 050 inch Lift 224
Exhaust Duration 050 inch Lift 230
Advertised Intake Duration 276
Advertised Exhaust Duration 282
Intake Valve Lift with Factory Rocker Arm Ratio 0.502
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.510
Lobe Separation (degrees) 110


Lunati - RRA1-232-242

Cam Style Hydraulic roller tappet
Basic Operating RPM Range 2,000-6,500 RPM
Intake Duration 050 inch Lift 232
Exhaust Duration 050 inch Lift 242
Advertised Intake Duration 290
Advertised Exhaust Duration 300
Intake Valve Lift with Factory Rocker Arm Ratio 0.510
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.525
Lobe Separation (degrees) 110

 

I am going to do this in the future. My mechanic said that ported L98 heads would be good enough and a CC 306 cam with the LT1 converted intake. Go to Tracy Scott Performance for more info. You can ask them questions at www.fastfreaks.com or www.nkyfba.com, they have their own forum there.

 

Your LSA needs to be greater then 110° for EFI. I would prefer 114° or at least 112°.

 

How about this cam?

http://www.compcams.com/Technical/Se...umber=08-305-8

Part Number 08-305-8
Engine -9999 Chevrolet
305ci-350ci
8cyl.
Grind Number CS 276H-R14
Description

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Intake Exhaust
Valve Adjustment 0.51 0.51
Gross Valve Lift 0.51 0.51
Duration At 0.006 Tappet Lift 276 290

--------------------------------------------------------------------------------

Valve Timing At 0.05
Open Close
Intake 0 40
Exhaust 53 -3

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These Specs Are For The Cam Installed At 110 Intake CL
Intake Exhaust
Duration At 0.05 220 230
Lobe Lift 0.34 0.34
Lobe Separation 114

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Recommended Valve Springs 986-16

 

CC305 (that cam) should be pretty good. I'm going with the CC304 on my 305ci LT1 project.

 

I'm using the comp 304 with tf23* heads on my L98 and I like it pretty well. If I could just get the chip tune sorted out I'd be fine. Now that it's january I don't think I'll be working on the bird for a few months.

 

Slayer,

What part# was the head? There seems to be quite a few options on the Summit site to choose from. Also, was the 304 enough or do you wish you had gone a little more agressive like with the 305?

Thanks for the comment.

 

Well I'm not sure what the part number is but I used a set for the 86 and older with 64cc chambers because I got them from a guy who bought them new and never used them. I kinda wish I had went with a bigger cam, but don't get me wrong I'm pretty happy with it. At the time I was getting a little short on funds and got a good price for this cam used. this combo pulls pretty well all the way to 5500rpm. I think it'll be better when I get my chip a little closer. I did use the trick flow springs for a few weeks but beacause they were on the edge for that cam I went with comp 986-16s. I also went with a b&m convertor that I had laying around for a few years with a stall speed of 2200-2400 rpm.

 

Did you have to replace the lifters as well? Also, what intake are you running? I am thinking that eveything is going to have to be redone at once because of the tear down time - do not want to do that twice.

 

No, I reused my factory rollers but my motor only had 43000 miles on it. I inspected them pretty well to make sure there was no scoring or flat spots or other problems before reinstalling them. I have the lt1 but I can't remember what year it was if that's what you mean. I don't think it matters what year you use in terms of performance. I did it all at once for the same reason. I've also got 1 3/4 slp headers.

 

Yeah, I have the 1"3/4 headers from SLP also. Today, I found out an interesting option. I talked to a performance shop today who will make a custom grind for $275 to match a set of trick flow heads along with all of the other mods I tell them that are on the car. I talked to trick flow today about what heads work best for our cars - the rep from trick flow was very helpful.

He recommended the pre-1987 heads though for the LT1 intake. Something about bolt pattern and the angle which the the center bolts bolt into the heads. Basically, the LT1 has to be retrofited for the pre 87 heads which should not be the hard I think. The heads I am going to go with are the CNC ported I think - he said a 15-20 HP gain due to the uniformity of the porting - It made sense to me after hearing the theory. This is all very new so I am learning with every converstation and sometimes every post here. A lot of fun.

Any thoughts on this?

 

I think you may have the head choice worded a little backwards. But that's ok. The intake is a little easier to modify and bolt up with 87 and later bolt pattern. John @ Lt1intakes.com did my intake and that is what he indicated. You should look at his site for more info. He's the expert, not me. As for cam selection, I'm in the same boat. I'm not sure which way to go yet. Good luck.

 

I actually have a friend who runs a automotive machine shop mill flats on my intake so it would work easier with the older heads. I would've gotten the later style but I ran into a good deal on these so I went for them. As I said about the cam, I'm pretty happy with the 304 overall but if I had happened on a better cam for the same price I might have went for it.

 

Sorry about the wording - still figuring this out.

When I talked to Trickflow - one of their people told me to go this route. He said that the center bolt valve covers did not work well with the rockers on their heads for what I wanted to do. He suggested the perimeter head and valve cover option for the rockers to work better and that I would not have leakage issues due to the raise edges around the head where the valve cover sits. The perimeter head bolt pattern is the pre 1987 model. He said that only two places would have to be worked on the LT1 head to work. It was fuzzy to me but it was something about a 75% angle verses a 90% angle for two of the bolts in the heads. The bottom line is more power and less problems in the long run. He also told me to go with 1.5 rockers which I thought would have had enough room to not cause problems.

Since I am new to this and the rep sells the product all day long - I had to at least listen to him thinking he is more in the know about their product than I am. The shop that sells the heads has been doing so for ten years and said the customer service line at trick flow is the way to go and they would set me straight.

If others have insight here - please help me out!

It was John Milican who suggested the trickflow heads. I will have to ask him about this before I assume this will work.

I like this forum for this reason - all the input is very helpful Perhaps I will get it close to being right the first time I attempt all of this.

 

What he meant about the angle is the middle set of bolts on either side of the manifold. I'm not sure of the angle but the newer style goes almost straight down into the head, whereas the older style is angled so the bolt head is pointing more towards the center of the mainfold. sort of like / this. sorry I can't give you a real picture. if you check out johns site you should get a better picture of what I'm talking about.

 

I personally was gonna go with the LT1 intake and comp cams 083068 cam (230* 340* .510/.540) with 1.6rr with AFR heads. I am hopping to make 450hp+ at the flywheel, with a 150 shot of nitrous i hope to hit low 11's.

 

Running centerbolt valve covers pretty much requires narrow body rockers. Besides that there isn’t much difference.

 

I know im raising this post from the dead, but I am in the same boat right now and was wondering if you guys ever found a good cam to use with the lt1 intake and the trickflow 23* heads. I got the ones with the dual valve springs so i don't have to worry about the lift, except I still want a daily driver.